The Devil is in the Details: A Case of Fulminant Giant Cell Myocarditis

Introduction

Giant cell myocarditis is a rare, rapidly progressive disease that requires a high degree of clinical suspicion. We report a case of fulminant giant cell myocarditis with profound cardiogenic shock requiring mechanical circulatory support and ultimately, successful heart transplant.

Case Report

A 53-year-old female with 11 prior pregnancies presented with chest pain and was found to have complete heart block and presumed NSTEMI with troponin-I of 6 ng/mL. Coronary angiogram revealed 85% stenosis of the right coronary artery which was stented, and a pacemaker was implanted for complete heart block; EF was 50% at that time. She was discharged but re-presented with worsening shortness of breath; troponin was 13 ng/mL and BNP was 2261 pg/mL. She was taken for catheterization which demonstrated patent stents but severe cardiogenic shock with cardiac index of 1.2 L/min/m². Intra-aortic balloon pump was placed and inotropes started but support was inadequate and she was transitioned to peripheral VA-ECMO with Impella. Emergent endomyocardial biopsy was performed with histology unequivocally diagnostic of giant cell myocarditis (Figure). Immunosuppression with steroids, thymoglobulin, and tacrolimus was initiated. She had recurrent ventricular tachycardia requiring cardioversion but ultimately, underwent urgent transplant evaluation and was listed status 1 (PRA 72%, BMI 21, blood type B+). She was successfully transplanted but had primary graft dysfunction requiring further VA-ECMO support for 10 days. She recovered normal graft function and was discharged on postoperative day 35.

Summary

Giant cell myocarditis presents with variable clinical symptoms but is frequently characterized by acute heart failure, cardiogenic shock, heart block, and ventricular arrhythmias. Definitive diagnosis requires endomyocardial biopsy. Mechanical circulatory support and transplant can be used successfully in fulminant cases of giant cell myocarditis.